Back to Search
Start Over
LES and URANS study on turbulent flow through 3 × 3 rod bundle with spacer grid and mixing vanes using spectral element method
- Source :
- Annals of Nuclear Energy. 161:108474
- Publication Year :
- 2021
- Publisher :
- Elsevier BV, 2021.
-
Abstract
- In this paper, the turbulent flow in rod bundles with spacer grid and mixing vanes in nuclear reactor core was studied using spectral element method with large eddy simulation (LES) and unsteady RANS (URANS) method. Combining with the radial periodical boundary conditions, the turbulent mixing phenomena in central subchannels were investigated, especially focusing on the flow field after the spacer grid and mixing vanes. Other than setting up long bare rod bundle to establish the fully developed turbulent flow, only a 2-cm-long bare rod bundle was extruded upstream the spacer grid and mixing vanes, while the fully developed laminar velocity profile was applied on the inlet surface for velocity boundary settings. The results indicate that both of the models could predict time-averaged velocity at 0.5Dh, 1Dh, 4Dh downstream mixing vanes properly, while the URANS model underestimate the root-mean-square (RMS) value of fluctuating velocity due to the inlet treatment effect. Furthermore, turbulent kinetic energy contour with transverse velocity vector was combined to investigate the behaviors of vortices formed by split-type mixing vanes, revealing the behavior of vortices for preliminary dynamic and mechanic analysis in design process of fuel assembly.
- Subjects :
- Materials science
Turbulence
020209 energy
Laminar flow
02 engineering and technology
Mechanics
01 natural sciences
010305 fluids & plasmas
Vortex
Physics::Fluid Dynamics
Nuclear Energy and Engineering
Bundle
0103 physical sciences
Turbulence kinetic energy
0202 electrical engineering, electronic engineering, information engineering
Reynolds-averaged Navier–Stokes equations
Mixing (physics)
Large eddy simulation
Subjects
Details
- ISSN :
- 03064549
- Volume :
- 161
- Database :
- OpenAIRE
- Journal :
- Annals of Nuclear Energy
- Accession number :
- edsair.doi...........73079a98dcbbd7754184a62de9fb8855